| Servlet that automatically scans chain configuration files
in the current web application at startup time, and exposes the result in a
Catalog under a specified servlet context attribute. The following
servlet init parameters are utilized:
- org.apache.commons.chain.CONFIG_CLASS_RESOURCE -
comma-delimited list of chain configuration resources to be loaded
via
ClassLoader.getResource() calls. If not specified,
no class loader resources will be loaded.
- org.apache.commons.chain.CONFIG_WEB_RESOURCE -
comma-delimited list of chain configuration webapp resources
to be loaded. If not specified, no web application resources
will be loaded.
- org.apache.commons.chain.CONFIG_ATTR -
Name of the servlet context attribute under which the
resulting
Catalog will be created or updated.
If not specified, it is expected that parsed resources will
contain
<catalog> elements (which will
cause registration of the created
Catalog s into
the
CatalogFactory for this application, and no
servet context attribute will be created.
NOTE - This parameter is deprecated.
- org.apache.commons.chain.RULE_SET -
Fully qualified class name of a Digester
RuleSet
implementation to use for parsing configuration resources (this
class must have a public zero-args constructor). If not defined,
the standard RuleSet implementation will be used.
When a web application that has configured this servlet is
started, it will acquire the
Catalog under the specified servlet
context attribute key, creating a new one if there is none already there.
This
Catalog will then be populated by scanning configuration
resources from the following sources (loaded in this order):
- Resources loaded from specified resource paths from the
webapp's class loader (via
ClassLoader.getResource()).
- Resources loaded from specified resource paths in the web application
archive (via
ServetContext.getResource()).
If no attribute key is specified, on the other hand, parsed configuration
resources are expected to contain <catalog> elements,
and the catalogs will be registered with the
CatalogFactory for this web application.
This class runs on Servlet 2.2 or later. If you are running on a
Servlet 2.3 or later system, you should also consider using
ChainListener to initialize your
Catalog . Note that
ChainListener uses parameters of the same names, but they are
context init parameters instead of servlet init
parameters. Because of this, you can use both facilities in the
same application, if desired.
author:
Matthew J. Sgarlata
author:
Craig R. McClanahan
author:
Ted Husted |
